Power-transmitting device.



No. 690,64l. v Patented Jan. 7, I902. l. H. DAVIS. POWEBTBANSMITTINGDEVICE.

(Application'flled A t. 24, 1901. (No Modei.) Y 2 Shoots-Shoat I.

No. 690,64I. P-ate'ntad' Ian. 7, 1902..

I. H; DAVIS. POWER TRANSMITTING DEVICE.

(Application flled Apr. 24,11901.) V (No Model.) 2 Sheat -Sheet 2.

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' UNITED STATES PATENT OFFICE.

ISAAC H. DAVIS, OF BOSTON, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TO EDWIND. MELLEN, OF CAMBRIDGE, MASSACHUSETTS.

POWER-TRANSMITTING DEVICE.

SPECIFICATION forming part of Letters Patent No. 690,641, dated January'7, 1902.

Application filed April 24, 1901.

To all whom it may concern: I Be it known that I, ISAAC H. DAvIs, ofBoston, in the county of Suffolk and State of Massachusetts, haveinvented certain new and useful Improvements in Power-TransmittingDevices, of which the following is a specification. 4

This invention relates to mechanism for starting and stopping andchanging the speed of adriven member, particularly such mem bers as aredriven by explosionengines and other constantly-operated motors.

The invention consists in novel means for applying a variable brakingpower to the controlling member of a differential gear.

Of the accompanyingdrawings, forming a part of this specification,Figure 1 represents an axial section of a power-transmittingdeviceconstructed in accordance with my invention. Fig. 2 representsa sideelevation thereof. Figs. 3, 4, and 5 represent sections on lines 3 3, 44, and 5 5 of Fig. 1. Fig.6 represents an axial section showing asecondmodification. i

The same reference characters indicate the same parts in all ofthefigures.

In the drawings, 1 represents the shaft of a constantly-driven motor,and 2 represents a sprocket-wheel driven thereby and adapted to beconnected to any-suitable mechanism which it is desired to drive, suchas the shaft of an automobile vehicle; Sprocket 2 is attached to a frameor casing 3, having bearings for the epicyclic or planetary gear mem-'bers 4 of a diiferential train. The shaft 1 has a gear 5 meshing withthe planetary gears 4 4, and a controlling-shaft 6," alined with shaft1, has a similar gear 7 meshing with said planetary gears. The casing 3is adapted to rotate concentrically about the shafts '1 and 6. The outerend of shaft 6 enters a'chamber 8, formed in an arm or bracket 9,extended from the motor-casing, and is provided in said chamber withnumerous parallel frictiondisks 10 10, having splines or keys 11 11,fitting in longitudinal keyways 12 12 on the shaft 6. Interposed betweenthe frictiondisks 10 10 on shaft 6 are stationary frictiondisks 13 13,having keys or splines 14 14 fitting in longitudinal keyways 15 15 inthe wall of the chamber 8. The disks 10 and 13 Serial No. 57,218. (Nomodel.)

are movable to a limited extent axially of the shaft 6,1 so as to packmore or less closely together, and the outer end of the stack is engagedby a longitudinally-movable block 16, held from'rotation by the keyways15, said block being engaged on its outer face by a cupshaped nut 17,having an internal thread engaging an external thread on the bracket 9,said cup-shaped nut forming the outer end wall of-the chamber containingthe disks. A

suitablelubricating liquid, preferably of a non-freezable nature, suchas a mixture of glycerin'and water, is contained in the chamber'S and isadapted to circulate through a cooler 18, consisting of a course of pipeconnected at its ends to the two ends of the chamher 8 and provided withheat-radiatin g flanges 19 19. The walls of the chamber 8 are alsoprovided exteriorl y with heat-radiating flanges 2O 20. 'Ascrew-propeller 21 is attached to the from the walls of the chamber 8.toform an annular passage 23 for the circulation of the liquid in contactwith the disks. The nut 17 is provided with a" sprocket --wheel 24,engaged by a chain 25 under the control ofthe attendant or driver,whereby the nut is r0- tated. The inward axial movement of the nut islimited by a stop-screw 26, which may be adjusted to regulate themaximum pres sure between the disks. A stuffed coupling 27 connects thenut 17 with the cooler 18, and longitudinal movement of the nut isallowed for by the resilience or spring of the cooler.

It is apparent that by rotating the nut 17 an adjustableuniformly-graduated braking effect may be exerted on the shaft 6 by theresulting increase or decrease of friction-between the rotating andstationary disks 10 13.

This friction may be made so slight as to be negligible or it may be sogreat as to arrest the rotation of the shaft 6. The resistance of thecarriage or other driven member being supposed to be considerable, it isapparent iioc that if no appreciable friction or braking action isexerted on the shaft 6 the bearing-case 3 of the planetary gears willremain stationary and the motion of driving-shaft 1 will be communicatedin full through said planetary gears to shaft 6. By gradually increasingthe friction on shaft 6 until the resistance to its rotation is equal tothe resistance to the rotation of the casing 3 the said casing will bestarted in rotation at a gradually-increasing speed until when saidresistances are equal the power of the motor-shaft will be equallydistributed between casing 3 and shaft (3. By still further increasingthe friction on shaft 6 its rotation will be uniformly arrested and thespeed of the casing 3 will be uniformly increased until when the shaft 6is brought to rest the casing 3 will receive the full power of the motorand will have the greatest speed of which it is capable from therelation of the gears. The liquid in chamber 8 and cooler 18 effects thelubrica tion of the friction-surfaces of the disks 1O 13, which is veryimportant in order to prevent their rapid wearing away and destruction,and it also serves to absorb the heat generated by the friction of saiddisks,which heat is dissipated into the atmosphere by the heat-radiatingsurfaces of the chamber and cooler Walls.

Fig. 6 represents a modification of my invention, characterized by achamber 8, containing a quiescent body of lubricatingliquid in contactwith the friction-disks 1O 13, an axially-sliding sleeve 33, mounted onthe outside of said chamber and having a chamber 34,also containing thecooling liquid and communicating with the disk-chamber through slots 35,and a spring 36, interposed between the sleeve 33 and an adjusting-nut37 on the end of the disk-chamber shell. The sleeve 33 carries the block16, which abuts against the end of the disk-stack, and longitudinalmovement is imparted to the sleeve in a direction to increase thefrictional pressure between the disks by the spring 36 and in adirection to relieve said pressure by a lever 38 under the control ofthe operator engaging said sleeve. The walls of the sleeve 33 areprovided with longitudinal heat radiating flanges 39, and the end ofshaft 6 passing outside of the sleeve is provided with an air-fan 40 to0001 these flanges. By adjusting the nut 37 the maximum pressure betweenthe friction-disks may be varied.

My device is shown as applied directly to the shaft of the motor; butthis need not necessarily be so, as various modifications may be made inthe arrangement of parts hereinbefore shown without departing from thespirit of my invention.

I claim 1 1. In power-transmitting apparatus, the zombination of adifferential transmitting device, a driving member for said device, adrivenunember,andacontrolling member,and a liquid-immersed frictiondevice for braking the controlling member.

2. In power-transmitting apparatus, the combination of a differentialtransmitting device, a driving member for said device, a driven. member,and a controlling member, a liquid-lubricated friction device forbraking the cont-rolling member, and a cooler for the lubricatingliquid.

3. In power transmitting apparatus, the combination of a differentialtransmitting device, a driving member for said device, a driven member,and a controlling member, a liquid-lubricated friction device forbraking the controlling member, a cooler for the lubricating liquid, andmeans operated by the movement of the controlling member for circulatingthe lubricating liquid through the cooler.

4. In powertransmitting apparatus, the combination of an epicyclictransmitting device, the driving,driven and controlling members for saiddevice, a friction device to variably brake the controlling member,means to vary the friction thereof, and a body of lubricating liquidimmersing said device.

5. In powertransmitting apparatus, the combination of an epicyclictransmitting device,the driving, driven and controlling mem bers forsaid device, a friction device to variably brake the controlling member,means to vary the friction thereof, a body of lubricating liquidimmersing said device, and a cooler for said liquid comprising anelongated pipe circuit.

6. In power-transmitting apparatus, the combination of an epicyclictransmitting device,- the driving, driven and controlling mem bers forsaid device, a friction device to variably brake the controlling member,means to vary the friction thereof, a body of lubricating liquidimmersing said device, a cooler for said liquid comprising an elongatedpipe-circuit, and means operated by the movement of said controllingmember for circulating the liquid through said cooler.

7. In power-transmitting apparatus, the combination of an epicyclictransmitting device,the driving, driven and controlling members for saiddevice, a shaft connected to the controlling member, a series offriction-disks connected with said shaft so as to rotate therewith, aseries of interposed friction-disks held against rotation, means to varythe friction between said disks, and a lubricating liquid immersing saiddisks.

8. In power-transmitting apparatus, the combination of an epicyclictransmitting device, the driving, driven and controlling members forsaid device, a shaft connected to the controlling member, a series offriction-disks connected with said shaft so as to rotate therewith, aseries of interposed friction-disks held against rotation, said disksbeing movable axially of the controlling-shaft,means to vary the axialpressure between said disks, and a stop to limit the maximum pressure;

9. In power-transmitting apparatus, the

combination of an epicyclic transmitting de adjustable stop to limit thepressure-increasvice,the driving, driven and controlling meming movementof said nut. 10 bers for said device, a shaft connected to the Intestimony whereof I have affixed my sigcontrolling member, a series offriction-disks nature in presence of two witnesses.

5 connected with said shaft so as to rotate there ISAAC H. DAVIS with, aseries of interposed friction-disks held Witnesses: against rotation, arotary nut adapted to vary R. M. PIERSON,

the axial pressure between said disks, and an H. L. ROBBINS.

